Thermoformable multilayer films and blister packs produced therefrom

ABSTRACT

A multi-layer film structure for use in forming blister packaging. The multi-layer structure includes a first polymeric layer having a first surface and a second surface, the first polymeric layer comprising a metalized polyethylene teraphthalate, a second polymeric layer having a first surface and a second surface, the first surface of the second polymeric layer disposed adjacent the second surface of the first polymeric layer, the second polymeric layer comprising a cyclic olefin or a homopolymer of chlorotrifluoroethylene, and a third polymeric layer having a first surface and a second surface, the first surface of the third polymeric layer disposed adjacent the second surface of the second polymeric layer, the third polymeric layer comprising polypropylene or polyvinyl chloride. A method of making a multi-layer film structure and a packaging structure are also provided.

This application is a divisional of U.S. application Ser. No.17/011,005, filed Sep. 3, 2020, which is a continuation of U.S.application Ser. No. 14/745,090, filed Jun. 19, 2015, which is adivisional of U.S. application Ser. No. 12/551,919, filed Sep. 1, 2009,the entire contents of each of which are hereby incorporated byreference.

FIELD

This document relates generally to multilayered films and morespecifically to a multilayered film having a chrome or mirror-likeappearance on at least one surface thereof. The films disclosed hereinexhibit excellent moisture barrier properties, thermoform well and aresuitable for producing blister packs for packaging a plurality oftablets, such as smokeless compressed tobacco products.

New forms of smokeless tobacco products have entered the market placerecently, or have been described, including products in the form ofgels, films and tablets. Designing packaging for use with a smokelesstobacco product in the form of a tablet provides unique challenges. Forexample, with tobacco-based products, moisture content can become anissue, since tobacco is, by its nature, hygroscopic. Child-resistance isalso another desirable property for packaging used with a smokelesstobacco product.

In the packaging of tablets for distribution to consumers, blister packsare frequently utilized. In particular, when dispensing pharmaceuticalor certain other consumer products, blister packaging is generallyfavored over loose or bottled tablets, for certainty in quantitydispensed, security of storage and convenience of use.

Blister packs are commonly formed by molding a thin sheet of syntheticplastic or laminated material into a multi-pocket or compartmenttray-like structure. This may be undertaken continually on-line followedby a filling and closure operation.

The pockets or compartments are commonly disposed in a rectangular gridarray. Typically, an individual compartment is intended to contain asingle item. Compartment contents may be accessed at random, or, incertain instances, in a prescribed sequence. A peripheral upstandingrim, ledge or ridge may be incorporated, to help stiffen the overalltray profile and further protect the contents of the compartments.

Blister packs are typically formed by molding resiliently deformablesynthetic plastics into a pre-configured array of multiple discretepockets or blisters. A tablet is captured or restrained within thepockets by a releasable, removable or frangible backing layer, typicallyproduced from a metal, such as aluminum foil, metalized plastics foil,or a laminated paper and foil combination. In a laminated paper and foilcombination, the paper is adhesively bonded in a laminated, multi-ply,overlay to the foil, and used as a lift-off release layer. As such, thepaper is intended to protect the underlying foil while the paper is inplace. To that end, the paper is bonded to the foil, and is nototherwise secured to the blister pack itself.

A variety of films have been used to form blister packs. Conventionalfilms for use for use in forming blister packs typically includepolymers such as polyvinyl chloride (PVC), polyvinylidene chloride(PvDC), and/or fluoropolymers.

Typically, films that are used solely as dust barriers include amonolayer sheet including only PVC. These films typically do not includeany additional polymer layers due to increased production costs thataccompany the use of the additional polymers. These films also cannot beused as effective moisture barriers because PVC is known to permit highlevels of moisture to penetrate the film. Therefore, PVC is unsuitablefor use alone in applications which require moisture protection.

Attempts have been made to overcome issues of moisture protection infilms. These attempts include the use of halogens and fluoropolymers infilms that also include PVC and PvDC. The halogens and fluoropolymerstypically include fluorine and polychlorotrifluoroethylene. Use of thehalogens and fluoropolymers allow the films to provide adequate moistureprotection and to be used as moisture barriers.

A film including fluoropolymers that is representative of a film that isan effective moisture barrier is proposed in U.S. Patent ApplicationPublication No. 2003/0203141 to Blum et al. Blum et al. uses a filmincluding a first adhesive layer including a styrene butadienecopolymer, a base, an outermost layer including cyclic olefincopolymers, and a fluoropolymer in an outer layer of the film. Blum etal. also uses acyclic olefin copolymers in the outer layer of the film.It is known that the cyclic olefin copolymers are subject to degradationif contacted with oils, organic and alkaline solvents, and heat. Becauseof this degradation, the outer layer of the film is subject todeterioration and poor performance.

Cyclo-olefin copolymers (COC) exhibit excellent transparency andmoisture permeation properties, in addition to heat resistance, chemicalresistance, solvent resistance, and rigidity. COP, a non-crystallinecopolymer, has the further advantage of being amenable to thermoforming.While these properties make COC desirable in packaging applications,thermoformed COC is sometimes susceptible to stress cracking whenexposed to alkaline environments. A multilayered film incorporating aCOC layer is proposed in U.S. Pat. No. 6,042,906 to Itoh et al. whichdiscloses a plastic container having a COC layer adhered to an olefinresin or an ethylene/vinyl copolymer layer. The COC layer is adhered tothe non-cyclic olefin layers with an adhesive resin.

Multilayer polymer films or laminates, produced for their aggregateproperties, often include “tie” layers of adhesive materials sincedifferent polymers usually do not readily adhere to one another.

Multilayered polymeric films or sheets may be produced by co-extrusion.U.S. Pat. Nos. 3,479,425; 3,959,431; and 4,406,547 describe co-extrusionprocesses. Multilayered films are usually co-extruded by passing two ormore melt streams of polymers through a die. The materials are fusedtogether into a layered structure and are allowed to cool. Onceextruded, plastic films can be shaped into containers by subjecting themto a thermoforming process. The construction of blister packaging orother articles of manufacture by thermoforming processes is well known.

Thermoforming is credited with producing packaging having highdurability and integrity. U.S. Pat. Nos. 4,421,721; 4,994,229;5,106,567; and 6,086,600 describe various thermoforming processes forplastic containers. Generally, a thermoforming process forms plasticcontainers and packaging structures by heating a sheet of plastic to adesirable forming temperature and shaping the plastic by subjecting itto vacuum or pressure shaping in a mold.

Thermoformed blister packaging commonly contains commercial articlesincluding food products, personal care products, and the like. U.S. Pat.No. 6,489,016 discloses multilayer packaging films of polyolefin. Alsoproposing such packaging materials and packages made therefrom are U.S.Pat. Nos. 6,383,582; 5,750,262; 5,783,270; and 5,755,081. The moisturebarrier properties of a film are an important characteristic inpackaging applications. Moisture transmission through a container mayadversely affect the contents, especially in applications where thepackaging contains pharmaceuticals, food products, compressed tobaccoproducts and the like.

Despite advances in the art, there is still a need, particularly inblister packaging applications, for thermoformable sheets and filmshaving suitable moisture barrier properties, a premium appearance andwhich are highly processable, for forming blister packs for use with aplurality of tablets, such as smokeless compressed tobacco products.

SUMMARY

Disclosed herein are multi-layer film structures for use in formingblister packs for packaging a plurality of tablets and for methods formaking such structures and blister packs.

In one aspect, provided is a multi-layer film structure for use informing blister packaging. The multi-layer structure includes a firstpolymeric layer having a first surface and a second surface, the firstpolymeric layer including a metalized polyethylene teraphthalate, asecond polymeric layer having a first surface and a second surface, thefirst surface of the second polymeric layer disposed adjacent the secondsurface of the first polymeric layer, the second polymeric layerincluding a cyclic olefin or a homopolymer of chlorotrifluoroethylene,and a third polymeric layer having a first surface and a second surface,the first surface of the third polymeric layer disposed adjacent thesecond surface of the second polymeric layer, the third polymeric layerincluding polypropylene or polyvinyl chloride.

In one form, the multi-layer film structure further includes a first tielayer disposed between the second surface of the first polymeric layerand the first surface of the second polymeric layer.

In another form, the multi-layer film structure further includes asecond tie layer disposed between the second surface of the secondpolymeric layer and the first surface of the third polymeric layer.

In yet another form, the first tie layer and the second tie layer eachinclude an adhesive lacquer.

In another form, the multi-layer film structure is a laminatedconstruction.

In another form, the multi-layer film structure has a density of from0.98 to 1.03 g/cm³.

In another form, the multi-layer film structure has a water vaportransmission rate of from 0.20 to 3.00 g/m²/24 hrs, as determined byASTM F-1249.

In another form, the first polymeric layer of the multi-layer filmstructure has a thickness of from about 25 μm to about 205 μm.

In another form, the second polymeric layer of the multi-layer filmstructure has a thickness of from about 75 μm to about 205 μm.

In another form, the third polymeric layer of the multi-layer filmstructure has a thickness of from about 25 μm to about 205 μm.

In another aspect, provided is a method of making a multi-layer filmstructure. The method includes the steps of forming a first polymericlayer having a first surface and a second surface, the first polymericlayer including a metalized polyethylene teraphthalate, forming a secondpolymeric layer having a first surface and a second surface, the firstsurface of the second polymeric layer positioned adjacent the secondsurface of the first polymeric layer, the second polymeric layerincluding a cyclic olefin, and forming a third polymeric layer having afirst surface and a second surface, the first surface of the thirdpolymeric layer positioned adjacent the second surface of the thirdpolymeric layer, the third polymeric layer including polypropylene orpolyvinyl chloride.

In one form, the step of forming the first polymeric layer includesextruding the first polymeric layer, the step of forming the secondpolymeric layer includes extruding the second polymeric layer, and thestep of forming the third polymeric layer includes extruding the thirdpolymeric layer.

In another form, the multi-layer film is coextruded.

In yet another form, prior to lamination, a first tie layer is disposedbetween the second surface of the first polymeric layer and the firstsurface of the second polymeric layer and a second tie layer is disposedbetween the second surface of the second polymeric layer and the firstsurface of the third polymeric layer.

In another aspect, provided is a thermoformed blister package formedfrom a multi-layer film structure, the multi-layer film structureincluding a first polymeric layer having a first surface and a secondsurface, the first polymeric layer including a metalized polyethyleneteraphthalate, a second polymeric layer having a first surface and asecond surface, the first surface of the second polymeric layer disposedadjacent the second surface of the first polymeric layer, the secondpolymeric layer including a cyclic olefin or a homopolymer ofchlorotrifluoroethylene, and a third polymeric layer having a firstsurface and a second surface, the first surface of the third polymericlayer disposed adjacent the second surface of the second polymericlayer, the third polymeric layer including polypropylene or polyvinylchloride, wherein the thermoformed blister package defines a pluralityof domed receptacle portions.

In one form, the domed receptacle portions contain compressed tobaccoproducts in the form of tablets.

These and other features will be apparent from the detailed descriptiontaken with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Further explanation may be achieved by reference to the description thatfollows and the drawings illustrating, by way of non-limiting examples,various forms, wherein:

FIG. 1 is a schematic cross-sectional view of a multilayer film for usein forming the blister packs disclosed herein;

FIG. 2 is a perspective view of a blister pack, in accordance herewith;

FIG. 3 is a bottom plan view of the blister pack of FIG. 2 ; and

FIG. 4 is a side plan view of the blister pack of FIG. 2 .

DETAILED DESCRIPTION

Various aspects will now be described with reference to specific formsselected for purposes of illustration. It will be appreciated that thespirit and scope of the packages and methods disclosed herein are notlimited to the selected forms. Moreover, it is to be noted that thefigures provided herein are not drawn to any particular proportion orscale, and that many variations can be made to the illustrated forms.Reference is now made to FIGS. 1-4 , wherein like numerals are used todesignate like elements throughout.

Definitions

The term “blister pack” is used herein to embrace a pre-formed orpre-configured packaging sheet or film, for example configured as ashallow tray, pre-profiled with multiple localized compartments orpockets. The individual compartment profile conveniently complementsthat of the intended contents, to ensure a snug relative fit. The pocketwall affords some resistance to impact, but is typically deformable toallow contents displacement and ejection, and modest cushioning action.

The terms “film” and “sheet” are used interchangeably throughout thisdisclosure, although sheet may also be used to refer to a film that isthicker than 100 microns. “Mils” refers to thousandths of an inch andmay be used to refer to a film thickness.

The term “child-resistant” relates to certain measures to impedeunauthorized pack opening or access to children, as might otherwisearise by casual or curious handling, as encountered in child play. Suchprovision represents a precautionary or deterrent measure, rather thannecessarily an absolute defense/

The term “tablet” is used in its common context, and refers to a solidcomposition made by compressing and/or molding a mixture of compositionsin a form convenient for buccal application.

Referring to FIG. 1 , one form of a multi-layer film structure 10 isshown. The multi-layer structure 10 includes a first polymeric layer 12having a first surface 14 and a second surface 16. First polymeric layer12 comprises a metalized polyethylene terephthalate. A first tie layer18 is provided having a first surface 20 and a second surface 22, firstsurface 20 of the first tie layer 18 being disposed on second surface 16of first polymeric layer 12. First tie layer 18 may comprise an adhesivelacquer, the adhesive lacquer serving as a tie layer, as those skilledin the art will recognize.

Multi-layer film structure 10 also includes a second polymeric layer 24having a first surface 26 and a second surface 28, the first surface 26of second polymeric layer 24 disposed on second surface 22 of first tielayer 18. Second polymeric layer 24 comprises a cyclic olefin or ahomopolymer of chlorotrifluoroethylene. A second tie layer 30 isprovided having a first surface 32 and a second surface 34. Firstsurface 32 of second tie layer 30 is disposed on second surface 28 ofsecond polymeric layer 24. As with first tie layer 18, second tie layer30 may comprise an adhesive lacquer, which may serve as a tie layer. Athird polymeric layer 36 is provided having a first surface 38 and asecond surface 40, wherein second surface 40 of third polymeric layer 25forms an outermost surface of film structure 10. As shown in FIG. 1 ,first surface 38 of third polymeric layer 36 is disposed on secondsurface 34 of second tie layer 30. Third polymeric layer 36 comprisespolypropylene or polyvinyl chloride. The first surface of the firstpolymeric layer can also form an outermost surface of the film. Themulti-layer film can have a density from 0.98 to 1.03 g/cm³, a watervapor transmission rate of from 0.20 to 3.00 g/m²/24 hrs, as determinedby ASTM F-1249, and each of said three polymeric layers can have athickness of from about 25 μm to about 205 μm.

In one form, first polymeric layer 12 may be a metalized layer ofpolyester, such as polyethylene terephthalate. The metalizedpolyethylene terephthalate may be an aluminum metalized polyethyleneterephthalate film prepared by a vacuum metalizing process. Biaxiallyoriented metalized polyethylene terephthalate is available under thetrademark Mylar®, which is produced by a joint venture of DuPont andTeijin Films. Advantageously, metalized polyethylene terephthalate isinert to water, serves as a moisture barrier and is unaffected by oils,greases and most aromatics. Metalized polyethylene terephthalate remainstough and flexible from −100° F. (−73.33° C.) to over 300° F. (148.88°C.).

The metalized layer may be formed on the first polymeric layer orapplied on the first polymeric layer. The metalized layer may be formedon the first polymeric layer by one or more of the processes ofmetallization, including vacuum deposition, indirect metallization,electro-less plating, electrolytic plating and lacquer painting.Typically, the metalized layer consists of at least one metal selectedfrom a group of metals consisting of aluminum, copper, silver, gold,brass and bronze. Owing to its highly reflective properties, aluminummetalized polyethylene terephthalate provides a surface that is nearlymirror-like.

The metalized layer may be coated with a fine metallic deposition,typically, aluminum in the range of 0.005 to 2 microns. The metaldeposition in such thin layers results in a metalized film with enhancedmoisture barrier properties with a loss of transparency of the filmresulting in a metalized semitransparent to opaque film.

In one form, first tie layer 18 may include an adhesive so as to serveas an adhesive tie layer. First tie layer 18 may be applied eitherdirectly onto either of the first polymeric layer 12 or second polymericlayer 24 by any appropriate means in the art, such as by coating. Anysuitable adhesive, such as polyurethane, epoxy, polyester, acrylic,anhydride modified polyolefin and blends thereof, may be employed. Onetype of adhesive includes modified polyolefin compositions having atleast one functional moiety selected from the group consisting ofunsaturated polycarboxylic acids and anhydrides thereof. Suchunsaturated carboxylic acid and anhydrides include maleic acid andanhydride, fumaric acid and anhydride, crotonic acid and anhydride,citraconic acid and anhydride, itaconic acid and anhydride and the like.Modified polyolefins suitable for use include compositions described inU.S. Pat. Nos. 3,481,910, 3,480,580, 4,612,155 and 4,751,270.

Other adhesive layers may include alkyl ester copolymers of olefins andalkyl esters of α,β-ethylenically unsaturated carboxylic acids such asthose described in U.S. Pat. No. 5,139,878. The modified polyolefincomposition may comprise from about 0.001 to about 20 weight percent ofthe functional moiety, based on the total weight of the modifiedpolyolefin or from about 0.05 to about 10 weight percent, or from about0.1 to about 5 weight percent. The modified polyolefin composition mayalso contain up to about 40 weight percent of thermoplastic elastomersand alkyl esters. In one form, first tie layer 18 may comprise anadhesive lacquer.

In one form, second polymeric layer 24 may comprise a cyclic olefin,such as a cyclo-olefin copolymer. Useful cyclo-olefin copolymers,collectively referred to herein as COC resins are known. For example,U.S. Pat. Nos. 5,912,070 and 6,068,936 disclose several cyclo-olefincopolymers, the disclosures of which are hereby incorporated byreference in their entirety. Suitable cyclo-olefin copolymers may alsoinclude copolymers of cyclo-olefin monomers and acyclic olefin monomers.

As is known to those skilled in the art, cyclo-olefins are mono- orpolyunsaturated polycyclic ring systems, such as cycloalkenes,bicycloalkenes, tricycloalkenes or tetracycloalkenes. The ring systemscan be mono-substituted or poly-substituted. In one form, the cyclicolefin may include at least one pendant organic group. The pendantorganic group may include alcohols, amines, carbonyls, ethers,hydrocarbons, nitrites, sulfides, and combinations thereof. Examples ofsuitable cyclic olefins include, but are not limited to, norbornene,dimethyl-octahydro-naphthalene, cyclopentene, (5-methyl) norbornene, andcombinations thereof.

In one form, the monomers can be made into homopolymer COC orpolymerized with acyclic comonomers, which may be referred to generallyas a crosslinker or simply as a comonomer. Examples of suitable acyclicolefin monomers which may be polymerized with the cyclo-olefins notedabove are ethylene, propylene, butylene and the like, or mixturesthereof. A preferred cyclic olefin is norbornene, and a preferredacyclic olefin for reaction therewith is ethylene. If the cyclic olefincopolymer includes norbornene, the norbornene may be included in anamount of from 10 to 70 mole percent or from 25 to 45 mole percent. Ifthe cyclic olefin copolymer includes ethylene, the ethylene may beincluded in an amount of from 30 to 90 mole percent or from 55 to 75,mole percent.

Cyclo-olefin polymers can be prepared with the aid of transition-metalcatalysts, e.g. metallocenes. Suitable preparation processes are knownand described, for example, in U.S. Pat. Nos. 5,912,070; 6,008,298;6,489,016; and 6,608,936, the disclosures of which are incorporatedherein in their entirety by reference.

Suitable cyclo-olefin copolymers are commercially available, examples ofwhich include Topas® 8007F04, manufactured by Ticona of Summit, NewJersey, Zeonex® from Zeon Chemicals of Louisville Ky., and Arton®, fromJSR Corporation of Tokyo, Japan. Mitsui Petrochemical Industries ofTokyo, Japan also produces suitable cyclo-olefin copolymers.

In another form, second polymeric layer 24 may comprise a fluoropolymer.Suitable fluoropolymers include, but are not limited to,ethylene-chlorotrifluoroethylene (ECTFE), ethylene-tetrafluoroethylenecopolymer, fluorinated ethylene-propylene copolymer,perfluoroalkoxyethylene, polychlorotrifluoroethylene (PCTFE) homopolymeror copolymer, polytetrafluoroethylene, polyvinylfluoride, polyvinylidenefluoride, and copolymers and blends thereof. In one form, thefluoropolymers include homopolymers and copolymers of PCTFE andcopolymers of ECTFE. As used herein, copolymers include polymers havingtwo or more monomer components. Such copolymers may contain up to 10%,and preferably up to 8% by weight of other comonomers, such asvinylidene fluoride and tetrafluoroethylene. Suitable fluoropolymers arecommercially available, an example of which includes the PCTFEfluoropolymers available under the trademark Aclar® from HoneywellInternational Inc. of Morristown, N.J. In one form, the fluoropolymer isa homopolymer of chlorotrifluoroethylene.

In one form, second tie layer 30 may also include an adhesive so as toserve as an adhesive tie layer. Second tie layer 30 may also be appliedeither directly onto either of the second polymeric layer 24 or thirdpolymeric layer 26 by any appropriate means in the art, such as bycoating. Any suitable adhesive, such as polyurethane, epoxy, polyester,acrylic, anhydride modified polyolefin and blends thereof, may beemployed. Modified polyolefin compositions having at least onefunctional moiety selected from the group consisting of unsaturatedpolycarboxylic acids and anhydrides may be employed. Such unsaturatedcarboxylic acid and anhydrides include maleic acid and anhydride,fumaric acid and anhydride, crotonic acid and anhydride, citraconic acidand anhydride, itaconic acid and anhydride and the like. Once again,suitable modified polyolefins include compositions described in U.S.Pat. Nos. 3,481,910; 3,480,580; 4,612,155; and 4,751,270.

As with first tie layer 18, other adhesive layers may include alkylester copolymers of olefins and alkyl esters of α,β-ethylenicallyunsaturated carboxylic acids such as those described in U.S. Pat. No.5,139,878. The modified polyolefin composition may comprise from about0.001 to about 20 weight percent of the functional moiety, based on thetotal weight of the modified polyolefin or from about 0.05 to about 10weight percent, or from about 0.1 to about 5 weight percent. Themodified polyolefin composition may also contain up to about 40 weightpercent of thermoplastic elastomers and alkyl esters as described inU.S. Pat. No. 5,139,878. In one form, second tie layer 30 may comprisean adhesive lacquer.

Third polymeric layer 36 may comprise polyvinyl chloride (PVC),copolymers and terpolymers of vinyl chloride, such as a terpolymer ofpolyvinyl chloride/polyethlene/polypropylene, and mixtures thereof. Asthose skilled in the art widely recognize, PVC is commercially availablefrom a wide variety of sources.

In an alternative form, a method to create a metallic outer surfacehaving a premium appearance on a blister pack may include the use ofmaterials like polypropylene/cyclic olefin copolymer/polypropylene orpolyvinyl chloride/cyclic olefin copolymer/polyvinyl chloride isprovided. The metallic layer may be created by depositing a coating onthe blister material through vacuum metalizing. The coating can beapplied to the blister material either before or after thermoforming ofthe blister receptacles. Before metalizing, a pre-coat or base coat maybe applied over the blister pack to fill in surface irregularities andsurface defects that may exist within the blister material. A topcoatmay then be applied over the metalized layer to protect againstscratches or abrasion. A bright metallic color can be produced, over themetalized layer, by adding color pigment to the top coat material.

Referring now to FIGS. 2 through 4 , in one form, the films disclosedherein are formed into a blister pack. The film structure may bethermoformed into a blister pack using techniques that are well known inthe art.

As shown, blister pack 100 includes a plurality of receptacles 102.Referring to FIG. 4 , each receptacle 102 may contain a tablet 50. Inone form, the plurality of receptacles 102 of blister pack 100 isarranged in at least two columns.

Referring now to FIG. 3 , as may be appreciated, the blister pack 100disclosed herein may provide a surface area 54 for the printing ofgraphics and product information.

The film is molded such that the blister has an outer surface, an innersurface and a cavity. After thermoforming, a tablet 50, which may be acompressed tobacco product, or the like, is inserted into the cavity andthe structure is heat sealed with a lid-stock film 42 by heat sealingthe outer surface of the lid-stock film 42 directly to the thirdpolymeric layer 36. In this form, the lid-stock film 42 may comprise asupport layer 46 adhered to the third polymeric layer 36 via a third tielayer 44, and a metallic foil layer 48 adhered to the support layer 46via a fourth tie layer 52. The support layer 46 may be comprised of athermoplastic material, such as a material selected from the groupconsisting of polyolefins, polyamides, polyesters, polystyrene,poly(vinyl chloride), polyvinylidene chloride, polyurethanes andcombinations thereof.

In another form, tablet 50, which may be a compressed tobacco product,or the like, is captured or restrained within receptacles 102, by areleasable, removable or frangible backing layer 56, typically producedfrom a metal, such as aluminum foil, metalized plastics foil, or alaminated paper and foil combination. In a laminated paper and foilcombination, the paper is adhesively bonded in a laminated, multi-ply,overlay to the foil, and used as a lift-off release layer. As such, thepaper is intended to protect the underlying foil while the paper is inplace. To that end, the paper is bonded to the foil, and is nototherwise secured to the blister pack 100 itself.

In this form, the foil is fused, by heat welding, such as by a heatedprofiled platen, to the receptacle 102, except for certain localizedareas, such as at the edges, which serve as a backing paper lift-offpoint for paper separation and removal from the foil. The paper overlayeffectively obscures the foil and impedes piecemeal foil and receptacleseparation.

Generally, the paper layer constitutes a tamper-resistant andchild-resistant layer to prevent casual blister pack content discharge,such as through inquisitive handling and experimentation. Once the paperoverlay is peeled back from the foil underlay, over a selected tabletreceptacle 102 of the blister pack 100, foil puncture is allowed.

To assist localized peeling of the protective paper backing layer, it isknown to apply a matrix or grid of perforations, say, upon packfabrication and assembly. Thus local removal of a paper backing coverportion overlying a particular receptacle 102 and local exposure of foiloverlying that pocket, allows content displacement and ultimateejection, upon foil tearing or rupture, by depressing the relevantresiliently deformable blister receptacle wall.

As may be appreciated, machines dedicated to blister pack productionthat are capable of high speed operation are envisioned for use in theproduction of blister pack 100.

As indicated, blister pack 100 may advantageously be employed to packagea plurality of dissolvable compressed tobacco products that are adaptedto be consumed orally. Compressed tobacco products of this type aredisclosed in U.S. Application Ser. No. 60/990,661, the contents of whichare hereby incorporated for all that they disclose. Such compressedtobacco products are formed from a composition that includes at leastone tobacco component, at least one flavorant, at least one sweetener,at least one filler-binder, at least one lubricant; at least onedesiccant and a glidant. The outer surfaces of the compressed tobaccoproducts packaged within blister pack 100 may optionally be coated,treated, embossed or debossed.

Advantageously, blister pack 100 is designed to be capable of high speedassembly, and may employ the attendant machines and processes associatedtherewith.

As may be appreciated, the blister packs disclosed herein can providethe following features: tamper prevention, surface area for graphics,and a premium finished appearance that provides a non-pharmaceuticallook.

The design of the blister packs disclosed herein allows for multiplequantities to be packaged. The forms contemplated may include 8, 10, 16,and 20 count packages.

All patents, test procedures, and other documents cited herein,including priority documents, are fully incorporated by reference to theextent such disclosure is not inconsistent with this disclosure and forall jurisdictions in which such incorporation is permitted.

While the illustrative embodiments disclosed herein have been describedwith particularity, it will be understood that various othermodifications will be apparent to and can be readily made by thoseskilled in the art without departing from the spirit and scope of thedisclosure. Accordingly, it is not intended that the scope of the claimsappended hereto be limited to the examples and descriptions set forthherein but rather that the claims be construed as encompassing all thefeatures of patentable novelty which reside herein, including allfeatures which would be treated as equivalents thereof by those skilledin the art to which the disclosure pertains.

1. (canceled)
 2. A method of making a multi-layer film structure, themethod comprising: forming a first polymeric layer having a firstsurface and a second surface; forming a second polymeric layer having afirst surface and a second surface, the first surface of the secondpolymeric layer positioned adjacent the second surface of the firstpolymeric layer; forming a third polymeric layer having a first surfaceand a second surface, the first surface of the third polymeric layerpositioned adjacent the second surface of the second polymeric layer;and forming a lid-stock film arranged between a flat film and themulti-layer film structure to provide support.
 3. The method of claim 2,wherein the first polymeric layer includes a metalized polyethyleneteraphthalate.
 4. The method of claim 2, wherein the second polymericlayer includes a cyclic-olefin.
 5. The method of claim 4, wherein thecyclic-olefin includes a cyclo-olefin copolymer, and the cyclo-olefincopolymer is a copolymer of norbornene and ethylene.
 6. The method ofclaim 2, wherein the third polymeric layer includes polypropylene orpolyvinyl chloride.
 7. The method of claim 2, further comprising:thermoforming the multi-layer film structure so as to define a pluralityof domed receptacle portions.
 8. The method of claim 7, furthercomprising: covering a plurality of cavities defined by the plurality ofdomed receptacle portions with the flat film, a flat surface of the flatfilm extending over each of the plurality of cavities, and the flat filmincluding a metallic foil.
 9. The method of claim 2, wherein the formingthe first polymeric layer includes extruding the first polymeric layerto form the first polymeric layer, the forming the second polymericlayer includes extruding the second polymeric layer to form the secondpolymeric layer, and the forming the third polymeric layer includesextruding the third polymeric layer to form the third polymeric layer.10. The method of claim 2, wherein the multi-layer film structure iscoextruded.
 11. The method of claim 2, wherein the forming the firstpolymeric layer, the forming the second polymeric layer, and the formingthe third polymeric layer forms the multi-layer film structure having alaminated construction.
 12. The method of claim 2, further comprising:positioning a first tie layer between the second surface of the firstpolymeric layer and the first surface of the second polymeric layer; andpositioning a second tie layer between the second surface of the secondpolymeric layer and the first surface of the third polymeric layer. 13.The method of claim 12, wherein the first tie layer and the second tielayer each include an adhesive lacquer.
 14. The method of claim 2,further comprising: forming a metalized layer on the first polymericlayer.
 15. The method of claim 14, further comprising: forming themetalized layer on the first polymeric layer by vacuum deposition,indirect metallization, electro-less plating, electrolytic plating,lacquer painting, or any combination thereof.